Heatable Tube

Abstract

The invention relates to a heatable tube (1) for conducting fluid, gaseous and/or pasty media, comprising an outer wall (10) that encloses an inner volume (11), and a heating element (2) which is arranged inside the inner volume (11) and which includes at least one first heating conductor (20a) that is surrounded by a first heating conductor insulation (21) insulating the heating conductor from the inner volume (11). The invention is characterized in that the first heating conductor insulation (21) insulating the heating conductor from the inner volume (11) is surrounded by a second heating conductor insulation (22).

Claims

1.-12. (canceled)

13. A heatable hose comprising: an outer wall enclosing an internal volume; and a heating element which is arranged within the internal volume; wherein the heating element has at least one first heating conductor which is surrounded with respect to the internal volume by a first heating conductor insulator and a second heating conductor insulator; and, wherein the outer wall comprises polyamide, polypthalamide, polyphenylene sulfide, or polyurethane.

14. The heatable hose as claimed in claim 13, wherein the heating element further comprises a second conductor which is surrounded with respect to the internal volume by the first heating conductor insulator.

15. The heatable hose as claimed in claim 14, wherein the first heating conductor and the second conductor are jointly surrounded with respect to the internal volume by the second heating conductor insulator.

16. The heatable hose as claimed in claim 13, wherein the first heating conductor is a first electrical heating conductor, and the second conductor is a second electrical heating conductor in the form of one of an electrically conductive cable, an electrically conductive thread or an electrically conductive element.

17. The heatable hose as claimed in claim 16, wherein the first electrical heating conductor and the second electrical heating conductor are PTC resistors.

18. The heatable hose as claimed in claim 13, wherein the first heating conductor insulator comprises a perfluoro (ethylene propylene) plastic, modified fluoroalkoxy, or perfluoroalkoxy alkane.

19. The heatable hose as claimed in claim 13, wherein the second heating conductor insulator comprises polyamide, polypthalamide, polyphenylene sulfide, or polyurethane.

20. The heatable hose as claimed in claim 13, wherein the outer wall and at least the second heating conductor insulator are connected by way of an adapter element.

21. The heatable hose as claimed in claim 20, wherein the adapter element comprises an adapter body which is connected to the second heating conductor insulator by way of a cohesive connection.

22. The heatable hose as claimed in claim 21, wherein the cohesive connection is one of a laser-welded connection, a rotary-welded connection, or an adhesive connection.

23. A heatable hose comprising: an outer wall enclosing an internal volume; and a heating element which is arranged within the internal volume; wherein the heating element has at least one first heating conductor which is surrounded with respect to the internal volume by a first heating conductor insulator and a second heating conductor insulator; and, wherein the first heating conductor insulator comprises a perfluoro (ethylene propylene) plastic, modified fluoroalkoxy, or perfluoroalkoxy alkane.

24. The heatable hose as claimed in claim 23, wherein the heating element further comprises a second conductor which is surrounded with respect to the internal volume by the first heating conductor insulator.

25. The heatable hose as claimed in claim 24, wherein the first heating conductor and the second conductor are jointly surrounded with respect to the internal volume by the second heating conductor insulator.

26. The heatable hose as claimed in claim 23, wherein the first heating conductor is a first electrical heating conductor, and the second conductor is a second electrical heating conductor in the form of one of an electrically conductive cable, an electrically conductive thread or an electrically conductive element.

27. The heatable hose as claimed in claim 26, wherein the first electrical heating conductor and the second electrical heating conductor are PTC resistors.

28. The heatable hose as claimed in claim 23, wherein the outer wall comprises polyamide, polypthalamide, polyphenylene sulfide, or polyurethane.

29. The heatable hose as claimed in claim 23, wherein the second heating conductor insulator comprises polyamide, polypthalamide, polyphenylene sulfide, or polyurethane.

30. The heatable hose as claimed in claim 23, wherein the outer wall and at least the second heating conductor insulator are connected by way of an adapter element.

31. The heatable hose as claimed in claim 30, wherein the adapter element comprises an adapter body which is connected to the second heating conductor insulator by way of a cohesive connection.

32. A heatable hose comprising: an outer wall enclosing an internal volume; and a heating element which is arranged within the internal volume; wherein the heating element has at least one first heating conductor which is surrounded with respect to the internal volume by a first heating conductor insulator and a second heating conductor insulator; and, wherein the outer wall and at least the second heating conductor insulator are connected by way of an adapter element comprising an adapter body which is connected to the second heating conductor insulator by way of a cohesive connection.

33. The heatable hose as claimed in claim 32, wherein the cohesive connection is one of a laser-welded connection, a rotary-welded connection, or an adhesive connection.

Description

[0032] Two exemplary embodiments and further advantages of the invention will be discussed below in conjunction with the following figures. In the figures:

[0033] FIG. 1 is a schematic sectional illustration of a heatable hose according to the invention as per a first embodiment; and

[0034] FIG. 2 is a schematic sectional illustration of a heatable hose according to the invention as per a second embodiment.

[0035] FIG. 1 is a schematic sectional illustration of a heatable hose 1 according to the invention as per a first embodiment. The heatable hose 1 is of cylindrical form along a longitudinal axis L and is illustrated with an open end on the left and with an end equipped with an adapter element 3 on the right.

[0036] The heatable hose 1 has an elastic outer wall 10 composed of an elastomer material, which outer wall encloses an internal volume 11 which, in this illustration, is furthermore delimited on the right-hand side by the adapter element 3 and is illustrated as being open toward the left. A medium such as for example a fluid can be conducted within said internal volume 11. In the case of an SCR system, the SCR hose 1 conducts an aqueous urea solution as fluid.

[0037] A heating element 2 in the form of an electrical heating element 2 is arranged, on the longitudinal axis L, in as far as possibly freely floating fashion in the internal volume 11 or fluid, which heating element is arranged so as to be uniformly spaced apart in a radial direction R from the inner side of the outer wall 10. This arrangement is however illustrated schematically for better comprehension, because the freely floating electrical heating element 2 adapts to the profile of the hose 1, which may also be curved depending on the application.

[0038] In this first exemplary embodiment, the electrical heating element 2 has a first electrical heating conductor 20a in the form of a thin copper cable or a thin copper-containing cable through which electrical current can flow in order to generate electrical heat losses and, by means thereof, heat the fluid in the internal volume 11. The first electrical heating conductor 20a is encased by a first heating conductor insulator 21 which chemically insulates said first electrical heating conductor with respect to liquids and at the same time permits a good transfer of heat to the internal volume 11. According to the invention, the first heating conductor insulator 21 is lined with a second heating conductor insulator 22 which additionally in particular chemically insulates the first heating conductor insulator 21 with respect to the internal volume 11 or the fluid such as for example the aqueous urea solution. In this way, the advantage of the direct transfer of heat of the freely floating electrical heating element 2 can also be utilized in usage situations with chemically aggressive fluids such as the aqueous urea solution of an SCR system.

[0039] The adapter element 3 has an adapter body 30 which is connected to the second heating conductor insulator 22 in pressure-tight fashion by way of a cohesive connection 31, such as for example a laser-welded or rotary-welded connection 31 or an adhesive connection 31.

[0040] FIG. 2 is a schematic sectional illustration of a heatable hose 1 according to the invention as per a second embodiment. Here, a second electrical heating conductor 20b is additionally arranged within the second heating conductor insulator 22 in order to increase the electrical heat losses and thus the heating power. The second electrical heating conductor 20b is likewise encased by the first heating conductor insulator 21. Here, the two heating conductors 20a, 20b in this exemplary embodiment are jointly encased by the first heating conductor insulator 21 and then by the second heating conductor insulator 22. Alternatively, the two heating conductors 20a, 20b may also be in each case spatially separately encased by the same first heating conductor insulator 21 or else by different first heating conductor insulators 21 and then by the common second heating conductor insulator 22 which, in this case, separates the two first heating conductor insulators 21 from one another, that is to say is also arranged between the two, 20a and 20b. This can simplify the production because the two heating conductors 20a, 20b with their respective first heating conductor insulator 21 can be produced separately and are thereafter brought together for the first time within the second heating conductor insulator 22.

[0041] Alternatively, the second electrical heating conductor 20b may also be used as an electrical conductor 20b for other purposes, such as for example for signal transmission or for an electrical feed to an electrical heating element (not illustrated). Then, the electrical resistance of the second electrical conductor 20b is correspondingly set such that the focus is on the as far as possible loss-free transmission of electrical energy rather than the generation of electrical current heat losses.

LIST OF REFERENCE SIGNS

Part of the Description

[0042] L Longitudinal axis [0043] R Radial direction, perpendicular to longitudinal axis L [0044] 1 (Electrically) heatable hose, SCR hose [0045] 10 Outer wall [0046] 11 Internal volume [0047] 2 (Electrical) heating element [0048] 20a First (electrical) heating conductor [0049] 20b Second (electrical) (heating) conductor [0050] 21 First heating conductor insulator [0051] 22 Second heating conductor insulator [0052] 3 Adapter element, connector element, quick connector [0053] 30 Adapter body, connector body [0054] 31 Cohesive connection between second heating conductor insulator 22 and adapter body 30, laser-welded connection, rotary-welded connection, adhesive connection